Sperm transport and endometrial inflammatory response in mares after artificial insemination with cryopreserved spermatozoa.

This study aimed to determine whether the insemination site and dose with cryopreserved sperm of reproductively normal mares affect the sperm population in uterine tubes and the intensity of endometrial inflammatory response. Experimental subjects were estrous mares inseminated, in the mid-uterine body (Body) or the tip of the uterine horn (Tip), ipsilateral to the dominant follicle, with one 0.5 mL straw with 50 × 106 sperm (50) or with eight straws with 50 × 106 sperm/straw (400). Mares were slaughtered 2 h, 4 h and 12 h after artificial insemination (AI) and randomly assigned to following groups: Body 50 (n = 19) (2 h, 4 h or 12 h); Tip 50 (n = 29) (2 h, 4 h, or 12 h); Body 400 (n = 24) (2 h, 4 h, or 12 h); Tip 400 (n = 21) (2 h, 4 h, or 12 h). A Control group (n = 16) was not inseminated. After slaughter, uterine tubes were separated from uterus, and uteri and tubes flushed with phosphate-buffered saline (PBS). After flushing, an endometrial sample was collected from ipsilateral and contralateral horns and mid-uterus body for further histopathological examination. A sample of each uterine tube flushing was examined for sperm count, and a sample of each uterine flushing was used for polymorphonuclear neutrophils (PMNs) count. Data were analyzed using PROC GLM from SASv9.4. Insemination time, site, sperm dose, and their interactions were considered independent variables and sperm and PMNs numbers dependent variables. Deep horn insemination increased ipsilateral uterine tube sperm number without an increase in the inflammatory reaction compared with the uterine body insemination. The higher the insemination dose, the higher the uterine tubes' sperm number and inflammatory reaction, with a quicker resolution. In conclusion, the insemination site and dose affected sperm in the uterine tubes, while post-insemination time and dose influenced the inflammatory reaction.

Histomorphometric and vascular changes in equine endometrium after the infusion of conceptus fragments.

This experiment aimed to verify if the proteins present in a 13th day conceptus induce changes in the equine endometrial ultra-structure, histology, and vascularization, two days after its infusion. Ten healthy cyclic mares were used. Once estrus was confirmed, mares were examined daily to detect ovulation (day 0). After ovulation, mares were examined daily until day seven by transrectal palpation and B-mode and Doppler ultrasonography. In this first cycle, intrauterine biopsies were collected at day seven after ovulation, constituting the Cyclic group (n = 10). In the second cycle, the same mares daily were examined until ovulation was detected. After ovulation, mares were examined daily by transrectal palpation and B-mode and Doppler ultrasonography until day 7. On day 5, after ovulation, fragments from previously collected 13-day-old concepti were infused into the uterus of each mare. Intrauterine biopsies were collected at day 7 in all mares (n = 10), constituting the Fragment group. The percentage of ciliated and flattened cells decreased in the Fragment group. Protruded cells, superficial and intraglandular secretion, glandular lumen and diameter, blood vessel diameter, endometrial vascularization, and immune cells were higher in the Fragment group than in the Cyclic group. In summary, proteins of 13th day equine conceptus fragments infused at day five after ovulation signaled histological and vascular changes in the endometrium at the 7th day after ovulation.

Tissue preservation and cell culture of Przewalskii´s horse (Equus przewalskii): an endangered species / Preservação de tecidos e cultura de células do cavalo de Przewalski (Equus przewalskii): uma espécie em extinção

The Przewalskii´s horse or Mongolian wild horse (Equus przewalskii, Poljakov, 1881) is presently the only species of wild horse in existence. Originally from Asia, it is, classified as in extremely high risk of extinction which puts the species in the seriously threatened category. The aim of this work was the preservation of tissues and the development of cell cultures from tissue samples obtained from a Przewalskii´s horse after its death. Biopsies of skin, skeletal and cardiac muscle, and ear cartilage were removed from a recently dead horse, added to Phosphate Buffer Saline (PBS) and refrigerated until processing. Some of the samples were frozen in liquid nitrogen and the other was grown as explants to generate fibroblast cell monolayers. The cell cultures obtained, were subsequently propagated with low passages, and frozen in liquid nitrogen, thus avoiding genetic and phenotypic alterations. The tissues and cell cultures were thawed to ascertain their viability by checking its progressive grow in a flask. It was not possible to obtain cultures from cardiac muscle. A bank of tissues and cells from the single Przewalskii´s horse that existed in Uruguay was generated, and can be used for scientific purposes and for the conservation of the species in the future